This invention relates primarily to jump ropes and more particularly to jump ropes using a ball bearing assembly connecting the rope to the handle.
While the structure of jump ropes has improved over the years from the beginning models which feature a simple rope. More sophisticated structures were then provided wherein a simple handle was tied or otherwise crudely attached to each end of the rope. More recently jump rope manufacturers have advertised and sold more sophisticated models having a variety of ball bearing attachments between the rope and the handle such as those disclosed in U.S. Pat. No. 4,101,123 issued to Anthony Jul. 18, 1978 and U.S. Pat. No. 5,749,812 issued to Feciura and Lee on May 12, 1998. In each of the latter, the use of a ball bearing attachment obviates earlier problems of the rope twisting against the handle or the users"" hand which diminishes the play value of the jump rope. And while both of these inventions were vast improvements over prior art, they each have no means for easily adjusting the length of the jump rope or the speed at which can be rotated.
Modern jump ropes utilize a thin plastic coated flexible wire as the rope and the combination of this thin rope and a ball bearing attachment can raise the speed of rotation beyond the user""s ability to manage it. This factor can also diminish the play value of the jump rope. The present invention seeks to improve on prior art ball bearing jump ropes by adding adjustment means for both the length of the rope and the speed at which it may be oscillated.
The primary purpose of the invention is to provide a jump rope which can be adjustable as to the length of the rope and to the speed of oscillation.
It is a further purpose of the invention to provide a light weight hollow handle with a gripping surface and ventilation holes therein.
It is a further purpose of the invention to provide an adjustable friction brake to moderate the speed at which the jump rope spins.
It is a further object of the invention to provide an index spring and pawl to act as a stop against the rotation of the friction brake adjustment so that the brake will remain at a fixed tension during use.
It is a further object of the invention to provide a locking means to permit the jump rope to be adjusted in length and to remain fixed in length after such adjustment.
As will be seen from the annexed drawings and the description herein, the present invention provides a simple and efficient design of jump rope which effectively and inexpensively cures the deficiencies inherent in prior art jump ropes. Modern materials such as plastic covered flexible wire ropes are utilized in the present invention. Such materials improve the play value and longevity of the jump rope since they allow the jump rope to be used longer between rope replacements and, with adjustment, allow the jump rope to be configured in size and speed to accommodate children of various ages, sizes and skill level.
These and other objects of the present invention are provided in a jump rope construction which features a handle of cylindrical shape and including a closed end and an open end, a knurled surface hand grip and ventilation holes. In a first embodiment, the closed end is defined by a ball bearing assembly through which an attachment shaft is axially fitted so as to protrude and hold a boss for attachment of a thin flexible wire rope. A crimp screw perpendicular to the axis of the boss intersects a hole through the boss into which the wire is inserted and locked by tightening the crimp screw. Unlike prior art jump ropes whose handles are axially aligned with the rope, the present invention handles are perpendicular to the axis of the flexible wire giving a more comfortable hand position as the user swings the handles.
In a second, preferred, embodiment a friction brake is provided wherein the attachment shaft protrudes through a threaded cap. The cap has a knurled outer rim to provide a gripping means by which it can be turned. The cap has a friction pad attached which contacts the top of the bearing assembly as the cap is tightened. This acts to brake the rotation of the bearing assemble and thus the jump rope. The cap is retained in its frictional loading position by an index spring and pawl which permits minute adjustments to the braking tension on the bearing assembly.